This invention relates to an assembly configured to support a keyboard user""s forearms and wrists while allowing the user substantially full mobility of his forearms and hands for comfortably and effectively operating a keyboard and mouse. The assembly functions generally to reduce body fatigue and stress and more particularly to reduce the incidence of carpal tunnel syndrome and other occupational cumulative trauma disorders to the forearm and wrist.
Various structures are described in the prior art for supporting the arms of a keyboard user to minimize body fatigue, e.g., shoulder, back, neck, wrist etc. The known devices are generally bulky and awkward to use and limit a user""s ability to effectively manipulate a keyboard.
The present invention is directed to an assembly for supporting a user""s forearms and wrists while still allowing substantially full mobility of the user""s forearms and hands to enable him to comfortably and effectively operate a keyboard and mouse. More particularly, embodiments of the invention are specially configured to support a user""s forearms and wrists while providing sufficient freedom of motion to permit the user to move his arms in an essentially natural manner as if they were not supported.
An assembly in accordance with the present invention includes left and right subassemblies, each including an armrest. Each subassembly is configured to enable the armrest to (1) move laterally and longitudinally relative to a keyboard mounted on the surface of a support plate, (2) swivel about multiple axes oriented substantially perpendicular to said surface, and (3) tilt about an axis oriented substantially parallel to said surface. xe2x80x9cLateralxe2x80x9d, as used herein, refers to side-to-side motion, i.e., substantially parallel to the key rows of a keyboard. xe2x80x9cLongitudinalxe2x80x9d, as used herein, refers to motion essentially perpendicular to the key rows.
A preferred subassembly in accordance with the invention includes a post mounted for lateral motion along the surface of a keyboard support plate. The first end of a first link is coupled to the post for enabling the link to swivel around a first axis oriented substantially perpendicular to the support plate surface. A second link has a first end coupled to a second end of the first link for enabling the second link to swivel around a second axis oriented substantially perpendicular to said surface. The preferred subassembly further includes an armrest and means supporting the armrest on a second end of the second link for enabling the armrest to swivel around a third axis oriented substantially perpendicular to said surface and tilt around a fourth axis oriented substantially parallel to said surface.
In accordance with a preferred embodiment of the invention, the range of swivel movement around at least one of the aforementioned first, second, and third axes exceeds 360xc2x0. The range of tilting around said fourth axis is preferably limited to about xc2x120xc2x0.
A preferred armrest in accordance with the invention is contoured to comfortably support a user""s forearm substantially horizontally, i.e. parallel to the aforementioned plate surface. The armrest preferably includes a central floor for supporting the user""s forearm and spaced first and second upstanding side walls for cradling the forearm to enable the user to easily exert lateral and longitudinal forces for readily moving the armrest to a desired position. The upstanding sidewalls help maintain the user""s wrist and forearm in alignment. The forward portion of the armrest floor preferably droops downwardly enabling the user to readily manipulate the keyboard without requiring any unusual wrist flexure. The inner surfaces of the armrest floor and side walls are preferably cushioned, e.g., by foam padding, to enhance user comfort.
Each subassembly post is preferably configured to telescope in order to set the armrest at a desired height above the support plate surface. The posts of the left and right subassemblies are preferably mounted along a guidepath adjacent to the plate surface for lateral movement to enable the user to move his forearms in a natural manner as if they were unsupported.
A support plate in accordance with the invention can comprise a desk or table top or a portable plate. Regardless, it typically defines a primary surface area for supporting an independent keyboard or laptop computer proximate to the left and right arm support subassemblies. Additionally, the support plate preferably includes a hinged plate portion defining a secondary surface area for supporting a pointing device, e.g., a mouse. The plate portion is preferably hinged so that the secondary surface area can be adjustably tilted relative to the primary surface area to facilitate user control of the pointing device.